You mean Recoleta (THE place to sit outside at a cafe) and dulce de
leche, which can be found at any of the many branches Freddo has throughout
the city. Nitpicks aside, it's good advice.

La boca/caminito and San Telmo with the sunday's antique market in
Plaza Dorrego. Avenida de Mayo for architecture buffs (french, spanish,
fin-de-siecle). Museo Nacional de Bellas Artes for many good paintings
(Degas, Van Gogh, Modigliani, Zurbaran, ...). a walk in Palermo (parks,
lake). Florida, the street closed to car traffic (go on a working day).
Tango: San Telmo or Balvanera for fancy stuff of dubious authenticity; a
real tangueria (ask at any hotel) to see how real people dance.
Alex